1. Field of the Invention
The present invention relates to a heavy oil emulsion fuel combustion apparatus for public utility or industrial use, such as a heavy oil emulsion fuel combustion boiler, a heavy oil gasifying combined plant arranged to dehydrate water content in the fuel and then gasify the resulting fuel, etc.
2. Description of the Prior Art
The construction of a conventional heavy oil emulsion fuel combustion boiler is illustrated in FIG. 6. In the boiler illustrated in FIG. 6, a heavy oil emulsion fuel 101 is supplied from a fuel tank 100 directly to a burner in a main body 10 of the boiler. To the burner there is supplied an atomizing steam (burner atomization steam) 9 in the heavy oil emulsion fuel 101 to thereby atomize the heavy oil emulsion fuel 101 up to particles whose size enables easy combustion thereof.
Thereafter, the fuel 101 is combusted within the main body 10 of the boiler. On the other hand, another steam 8 is supplied to within the main body of the boiler in order to blow away, for example, ashes that attach onto the heat transfer pipes and the like within the main body 10 of the boiler. The exhaust gas 11 that is produced after combustion made within the main body 10 of the boiler is released from a chimney 50 into the atmosphere through a denitration unit 20, dedusting unit 30 and wet desulfuration unit 40.
In the conventional technique, although as mentioned above the heavy oil emulsion fuel 101 can be supplied at normal temperature to the main body 10 of the boiler, since approximately 20% to 30% of water content is contained in the heavy oil emulsion fuel 101 and the heat for evaporating this water content within the main body 10 of the boiler is necessary, the boiler efficiency decreases.